Grate-bar



(No Model.)

N. L. AUSTIN. GRATE BAR.

No. 311,633 Pa ented-Feb; s, 1885.

lhvrinn Snares NORMAN L. AUSTIN, OF NORWALK, CONNECTICUT.

Parent @rrrcie.

GRATE-BAR.'

3PECIFICATION farming part of Letters Patent No. 311,633, dated February 3, 1885.

Applica ion filed March 31, 1884. (No model.)

To all whom it may concern.-

Be it known that I, NORMAN L. AUs'rIN, of Norwalk, in the State of Connecticut, haveinvented an Improvement in Grate-Bars, of

have been grooved transversely and longitudin-ally. The clinkers are liable to adh re to the surfaces of the cast-iron bars, and the heat warps such bars and they become disin tegrated in their upper surfaces. 1 make the body of the grate-bar of cast-iron and the surface of short sections of wrought-iron or steel, the two being intimately united and the wrought meta-l surlace being'next to the fire, and preferably made in comparatively short lengths, so as not to be warped by unequal expansion. The result of this mode of construction is that the wrought-iron or steel, becoming soft or melting at a much higher temperature than the cast-iron, the cliukers do not adhere or the bars bu rn out or become oxidized as rapidly as cast-iron. The wroughtiron or steel being more dense and homogeneous than cast-iron, there are not pores, as in the cast-iron, to become filled with oxide and foreign substan es, and the surfaces of the bars retain a smoothness that is very advantageous in raking or slicing the fire. The cast-iron body of the bar is suiticiently far below the fire to remain comparatively cool and free from injury. The expansion or contraction of the wrought metal does not injure the bar, because the sections are short.

In the drawings, Figure 1 is a side View of a grate-bar with my improvement, and Fig. 2 is a cross-section of the same.

The body a. of the grate-bar is of cast-iron and the surface I) is of wrought-iron or steel. The parts are rigidly united by dovetailed groove and rib c. It is preferable to roll the gratebar b of iron or steel with the rib 0 upon its lower edge, and there to introduce such portions 1) into core-print recesses in the mold, and cast the iron so that it runs around the dovetailed rib and clamps the same. The groove may be in the wrought -iron and the rib upon the castiron. The wroughtiron or steel surface to the cast-iron body should be in comparatively short sections, as shown, so that the grate-bar may not be warped by unequal expansion or contraction, the spaces between the sections being sufli cient to allow of the expansion.

I do not claim a grate-bar in which the surface is composed of a continuous bar of Wrought-iron united to the cast-iron by dovetailed projections or by the cast metal pass ing into holes. In this case the wrought-iron bar, being exposed to the greatest heat, expands and either warps or breaks the cast metal.

I claim as my invention The grate-bin having a body of cast-iron and a firesurface composed of short sections of wrought-iron or steel connected to the castiron body, substantially as set forth.

Signedby me this th day of March, A. D. 1884..

NORMAN L. AUSTIN.

Witnesses:

SAML. S. BAILEY,

K. SnLLnoK. 

